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2020 Engine Kits & Rotating Assemblies

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Results 1 - 24 of 35

Hot Rods Complete Bottom End Rebuild Kits

When it's time to do a rebuild, Hot Rods complete bottom end rebuild kits are less expensive and longer lasting than OEM. These kits have all that you need to get back on track and are easy to put together. Each kit contains a crankshaft, main bearing/seals, and a complete gasket set. Water pump seals are not included. Great performance parts from Hot Rods will have you going, going, strong!

5.0 out of 5 stars ( 2 )

$534.38

$1,238.04

Summit Bucks

Namura Technologies Top-End Repair Kits

Top-end rebuilds can help to improve the performance of your ride, and Namura Technologies top-end repair kits will keep your ATV, UTV, or off-road motorcycle running in peak condition! They include everything you need: pistons, top-end gasket kit, and wrist pin bearings (where applicable) in one convenient, time-saving package. Namura kits are available for a wide variety of makes and models, with specific bore and compression ratio parts to service your specific vehicle. Choose to do your rebuild with repair kits from Namura Technologies—the people who make pistons with attitude!

5.0 out of 5 stars ( 1 )

$59.99

$239.99

Vertex Complete Engine Rebuild Kits

Manufactured in Italy, Vertex pistons, both cast and forged, are the premier choice and highest quality aftermarket replacement and performance pistons for dirt bikes, ATVs, and UTVs. Vertex also leads the way in manufacturing high performance gaskets for dirt bikes, ATV, UTV, snowmobiles, and PWCs. Conveniently, Vertex offers a huge number of complete engine rebuild kits, each of which will save you time and money over trying to match up the correct components and buying them separately. Oversized pistons are available in some kits. Choose a kit designed for your powersports vehicle. Kits include: * Crankshaft * Piston kit * Complete engine gasket kit * Oil seal kit * Main bearing and seal kit * Water pump rebuild kit * Transmission bearing kit * Countershaft bushing/seal kit * Camshaft chain where applicable * Counter balancer bearing kit where applicable * Wrist pin bearing where applicable

5.0 out of 5 stars ( 1 )

$433.46

$963.35

Scat Modern Muscle Engine Rotating Assemblies

Scat Modern Muscle engine rotating assemblies are available with high-quality Scat forged 4340 crankshafts and I-beam or H-beam connecting rods with 7/16 in. cap screw bolts. For maximum power and reliability, Scat adds rod and main bearings from King, Federal Mogul, or Clevite 77, depending upon the application, and pistons and piston rings made by such well-known manufacturers as SRP/JE, Ross, KB, Mahle, Diamond, and Probe.

4.67 out of 5 stars ( 3 )

$2,307.99

$2,814.99

Cylinder Works Standard Bore Cylinder Kits

Eliminate the wait with Cylinder Works standard bore cylinder kits. They arrive ready to install, eliminating the hassle of sending out your cylinder for re-plating or boring, and they're competitively priced compared to typical re-plating costs. These cylinders look virtually identical to your OEM parts. Cylinder Works standard bore cylinder kits come in model-specific kits, so choose the one that best fits your application. Features include: * Super-convenient--just purchase and install * Nickel silicon carbide plated for long life * Honed to exact size for easy piston installation * Complete with gaskets, cylinder, and piston kit * No machine work required

4.5 out of 5 stars ( 2 )

$395.25

$634.99

Cylinder Works Power Valve Kits

If you have a broken power valve on your off-road machine, Cylinder Works power valve kits offer you quick and affordable access to OEM-quality replacements. Standard bore and a big bore version are available to provide long-lasting quality you can depend on. Regulate your exhaust port to reach optimal power and rev level ride after ride with Cylinder Works power valve kits.

1.0 out of 5 stars ( 1 )

$206.77

$323.29

Vertex Replica Piston Kits

Quality you can see, power you can feel—Vertex Replica piston kits are choice replacements for precision performance. Available in 2- and 4-stroke, the Replica piston kits feature both cast and forged manufacturing processes, supplying the highest quality to meet your needs. And, Vertex offers A, B, C, and D sizes, so you can choose the proper fit for your cylinder. The difference in the sizes is 0.01mm (0.0004 in.) increments, with A being the smallest and D the biggest. Vertex Replica piston kit notes: * 2-stroke piston kits are gravity cast aluminum alloy with 18 percent silicone content, which produces an extremely light but very strong piston * 4-stroke pistons are forged from 2618 aluminum for superior strength and durability * All pistons are heat-treated with a T-5 hardening and tempering cycle * All piston skirts are treated with a high-tech molybdenum disulfide (MOS2) coating for faster break-in time and increased piston life * Standard pistons and rings are OEM replacements * Kits include piston, rings, wrist pin, and circlips

Not Yet Reviewed

$168.30

$198.63

S&S Cycle M8 Big Bore Cylinders

S&S Cycle M8 big bore cylinders are bolt-on sets for Milwaukee 8 models. They are available in a Wrinkle Black finish with or without highlighted fins. Select the set you would like.

Not Yet Reviewed

$662.95

$854.06

S&S Cycle 131 in. Big Bore Kits

S&S Cycle 131 in. big bore kits are aimed at the Milwaukee Eight platform for 2017 and newer big twins—and open up a whole new level of performance for these engines. When paired with an S&S 4.625 in. stroker flywheel (sold separately), engine will be a true 131cubic inches. S&S builds their big bore kits and cranks to much tighter tolerances and with higher quality materials than the factory parts. If you're the proud owner of a Harley-Davidson® Milwaukee Eight big twin and have been waiting for just the thing to boost your M8's power—the wait is over! The S&S Cycle piston/cylinder kits will be a solid platform for massive power! Features and benefits: * Huge displacement increase means huge power increase * Bolt-on kit works with stock crankcases * 4 1/4 in. bore cylinders with a new 11:1 forged piston design * Original engine serial numbers are retained * Powdercoat finish match factory finish, giving the bike a "sleeper" advantage * Includes .045 in. multi-layered steel head gaskets * Retains stock engine height * Includes 131 in. Cam Cover Badge * Available with or without highlighted fins Note: This kit must be used with S&S Cycle stroker flywheels to achieve 131 in. displacement (P/N: 320-0605, 320-0620).

Not Yet Reviewed

$1,403.96

S&S Cycle 128 in. Big Bore Kits

The S&S Cycle 128 in. big bore kits are for Harley-Davidson® Milwaukee Eight engines to allow you to upgrade your M8 motor to the largest bore size possible—and without required machining of your cases. So ... go big or go home! These upgrade kits are as simple as big power gets! S&S Cycle 128 in. big bore kit features: * 114 in. to 128 in. big bore kit * Bolt-on kit, the largest cylinder bore possible without requiring machining of the crankcases * Cylinders are constructed from premium aluminum castings wit cast-in iron liners * Wrinkle black finish in highlighted and non-highlighted fin versions * Easy installation; no need to bore or split existing cases—just swap the cylinders! * 4.250 in. bore, 4.500 in. stroke * Forged pistons * 11:1 compression ratio * All necessary gaskets and hardware required for installation included

Not Yet Reviewed

$1,403.96

$1,405.76

Vertex Top-End Piston Kits

Vertex top-end piston kits are OEM-style replacements. These kits include everything needed to rebuild a top-end for the specific application selected. When applicable, the wrist pin bearing included is DLC-coated for added longevity. All piston skirts are coated with a high-tech molybdenum disulphide coating for faster break-in and increased piston life along with a T-5 hardening cycle. Rebuild your top-end without worries with Vertex top-end piston kits.

4.5 out of 5 stars ( 2 )

$104.36

$194.04

Cylinder Works Cylinders

Cylinder Works cylinders are your powersports alternative to OEM or re-plating. These standard bore cylinders are brand new—not remanufactured or replaced—and are nickel silicon carbide-plated cast aluminum to provide long life. They're precision-honed to the exact size to make your piston installation easier. Cylinder Works offers dirt bike and ATV enthusiasts quick and affordable access to direct fit replacement cylinders. Order the bore size recommended for your application.

Not Yet Reviewed

$360.19

S&S Cycle 883 to 1200cc Hooligan Cylinder Kits

An 883 to 1200cc Hooligan cylinder kit for a Harley-Davidson®, like the ones made by S&S Cycle, provides a significant increase in engine displacement, resulting in substantially more power and torque without requiring major engine modifications, making it a popular upgrade for riders seeking better performance on their Sportster 883, with benefits like increased horsepower—by boosting the engine size from 883cc to 1200cc, the Hooligan kit delivers a noticeable power gain, allowing for better acceleration and highway cruising capabilities. Typically these kits are designed as "bolt-on" upgrades, meaning they can be installed without needing extensive machining or engine rebalancing, making the process relatively simple and straightforward. Compared to a complete engine rebuild, a Hooligan kit is a cost-effective way to significantly improve your bike's power. When installing a Hooligan kit, it may be necessary to upgrade the clutch to handle the increased torque produced by the larger engine. Depending on the specific kit and your bike setup, you may need to adjust fuel injection mapping to optimize performance.

Not Yet Reviewed

$1,095.95

$1,999.95

S&S Cycle 1250cc Conversion Cylinder Kits

The S&S Cycle 1250cc conversion cylinder kits are suitable for a range of Harley-Davidson® models, including the Sportster, which can benefit significantly from the added power. These cylinder conversion kits provide a significant increase in engine power and torque compared to the stock engine, making the bike significantly faster with a more noticeable acceleration, especially on smaller models like the Sportster, while often being a relatively cost-effective upgrade that can be done without major engine modifications or requiring a complete engine rebuild. This is particularly beneficial for riders seeking more power without drastically changing their bike's character. Each kit is tailored with the necessary components for your specific bike model. Many 1250cc conversion kits are designed to be installed without requiring major engine modifications, making them a good option for DIY mechanics. In most cases, you can use your stock cylinder heads, cams, and other engine components with a 1250cc conversion kit. Select the kit designed specifically for your HD® model and engine to ensure proper fitment.

Not Yet Reviewed

$978.95

$1,045.95

S&S Cycle 1200cc to 1250cc Hooligan Cylinder Kits

Whether you are looking for better acceleration for everyday riding or more power for spirited driving, S&S Cycle 1200cc to 1250cc Hooligan cylinder kits provide a noticeable improvement. The larger displacement from 1200cc to 1250cc directly translates to more power, making the bike faster and more responsive, especially noticeable in acceleration and mid-range torque. These kits are designed to be "bolt-on" meaning they can be installed without needing to machine the engine cases or rebalance the crankshaft, making the upgrade process fairly straightforward. Each kit is tailored with the necessary components for your specific HD® model. Most Hooligan kits utilize the existing stock heads, pushrods, and fuel system, minimizing the need for additional parts or adjustments. Compared to a full engine rebuild or custom build, S&S Cycle's Hooligan kits are a relatively affordable way to significantly improve performance. Select the kit designed for your application needs.

Not Yet Reviewed

$1,709.95

$1,742.95

S&S Cycle 129 in. Big Bore Cylinder Kits

The S&S Cycle 129 in. big bore cylinder kits for a Harley-Davidson® motorcycle provides a significant increase in engine displacement, leading to substantially more power and torque, especially in the low and mid-range, while still maintaining compatibility with the stock crankcases for a noticeable performance boost. These kits essentially, give your bike a "bigger punch" without requiring extensive structural changes. Big bore kits often provide a noticeable improvement in low-end torque, making the bike more responsive in everyday riding situations. Most 129 in. kits are designed to work with stock crankcases and other engine components, simplifying installation. Many kits maintain the factory engine appearance with powdercoat finishes, giving the bike a subtle look that belies its enhanced performance. To fully optimize the performance gains from a big bore kit, additional tuning adjustments like adjusting the fuel injection system or changing the camshaft may be necessary. Each 129 in. big bore cylinder kit is tailored with the necessary components for your specific bike model. Select the kit that's designed specifically for your model and engine to ensure proper fitment.

Not Yet Reviewed

$1,595.95

$1,599.95

S&S Cycle 132 in. Big Bore Cylinder Kits

The S&S Cycle 132 in. big bore cylinder kits for a Harley-Davidson® motorcycle provides a significant increase in engine displacement, resulting in a substantial boost in horsepower and torque. This in turn makes the bike significantly faster with more power across the powerband, particularly noticeable in low and mid-range acceleration, while still maintaining compatibility with stock crankcases and retaining the stock engine height, offering a "sleeper" advantage with minimal visual modification. These big bore cylinder kits are typically designed to work with existing engine components like the stock head gaskets and flywheels. This makes installing them a significant investment compared to other performance upgrades. Each kit is tailored with the necessary components for your specific model. Many kits feature a powdercoat finish that closely matches the factory look. To fully optimize increased power, proper tuning with adjustments to fuel injection and ignition timing may be necessary. Order the 132 in. big bore cylinder kit designed specifically for your HD® model and engine to ensure proper fitment.

Not Yet Reviewed

$1,599.95

$1,649.95

S&S Cycle 750cc Big Bore Kits

The primary purpose of S&S Cycle's 750cc big bore kits is to enhance the performance of smaller engine models, particularly for the Street 500 or Street 750, giving them more power and acceleration. These stock bore cylinder kits are designed to increase the engine displacement by enlarging the cylinder bore, resulting in more power and torque compared to the stock engine, typically by converting a smaller displacement engine like a 500cc or 650cc into a 750cc unit. Many big bore kits are designed to be "bolt-on" upgrades, meaning they can be installed without requiring extensive engine modifications or machining, making them relatively easy to add to a motorcycle. Before ordering, make sure this kit is compatible with your specific street bike model.

Not Yet Reviewed

$869.95

S&S Cycle 865cc Big Bore Kits

S&S Cycle 865cc Big Bore kits are ideal for Royal Enfield 650 Twins. Designed for closed course racing competition, the kits include pistons, rings, pins, and sleeves. The high compression pistons feature a 7cc raised dome to achieve a compression ratio of 11:1 (from 9.5:1). Higher compression is a key factor in increasing performance.

Not Yet Reviewed

$849.95

S&S Cycle 132 in. Power Packages with Chain Drive Cam

S&S Cycle offers 132 in. power packages with chain drive cam for a variety of Harley-Davidson© street bikes from 2017 and up. These packages are the ideal combination of performance and savings designed to transform your engine from mild to wild. They combine S&S's biggest big bore cylinders with matched 550 cam/cam-plate/oil pump and everything else a high performance cam chest needs to make big, reliable horsepower. Additional details: * Available with 132 in. Big Bore pistons/cylinders * 550 lift cam for the perfect combination of horsepower and torque * Works with stock crankcases * Powdercoat finish matched to factory * MLS (multi-layered steel) head gaskets * Includes tappets, tappet cuffs, and high lift springs * Includes 132 cam cover badge * 132 Power Pack: Stock heads, 550 cam, stealth AC, stock throttle body, S&S manifold, power tune duals, MK45 muffler * Recommended for closed course competition racing

Not Yet Reviewed

$3,359.95

S&S Cycle 129 in. Power Packages with Chain Drive Cam

S&S Cycle offers 129 in. power packages with chain drive cam for a variety of Harley-Davidson© street bikes from 2017 and up. These packages are the ideal combination of performance and savings designed to transform your engine from mild to wild. They combine S&S's biggest big bore cylinders with matched 550 cam/cam-plate/oil pump and everything else a high performance cam chest needs to make big, reliable horsepower. Transform your 107 in. into a 129 in. monster. Additional details: * Available with 129 in. Big Bore pistons/cylinders * 550 lift cam for the perfect combination of horsepower and torque * Works with stock crankcases * Powdercoat finish matched to factory * MLS (multi-layered steel) head gaskets * Includes tappets, tappet cuffs, and high lift springs * Includes 129 cam cover badge

Not Yet Reviewed

$3,359.95

S&S Cycle 128 in. Power Packages with Gear Drive Cam

S&S Cycle offers 128 in. power packages with gear drive cam for a variety of Harley-Davidson© street bikes from 2017 and up. Kit details include: BIG BORE KIT: * 4.250 in. bore * Forged pistons * 11.1:1 compression ratio OIL PUMP/CAM PLATE: * Precision-machined from billet aluminum * Passage plugs removable for servicing * Independent scavenge sections for flywheel cavity and cam chest * Debris screens in both scavenge pickups * Magnet in cam chest to help stop debris from entering oil pump * Increased flow capacity on both feed and scavenge side * Pressure relief valve is adjustable with unit installed in engine * Kits now include updated oil pump with groove for optional OEM oil seal PUSHRODS: * Quickee pushrods with chrome covers TAPPETS: * Hand-assembled to exacting tolerances * Reduced valvetrain noise from start-up to shut-down * Close tolerances for low leak-down rates * Fast pump-up and superior high-RPM performance TAPPET CUFFS: * Hard anodized black coating * Billet aluminum construction * Stronger than stock material eliminates distortion * Improve tappet stability in high lift and high RPM situations CAM: * S&S 550 cam—designed for big bore applications * Gear drive kits provide improved cam timing accuracy and eliminate stock chain tensioner * Gear drive kits include outer drive gears VALVE SPRINGS: * Work well with cams up to .605 lift * High performance conical single-wire spring * Includes top collars, keepers, and valve seals/bottom collars

Not Yet Reviewed

$3,427.95

$3,460.95

S&S Cycle 124 in. Power Packages with Chain Drive Cam

The S&S Cycle 124 in. power packages with chain drive cam are the ideal combination of performance and savings to transform a Harley-Davidson® motorcycle without breaking the bank. Each kit is tailored with the necessary components for your specific HD® model. These kits offer significant benefits in terms of increased horsepower and torque, particularly noticeable in the mid-range and top-end of the rpm band, making for a more powerful and responsive riding experience, especially when paired with other performance upgrades like ported heads and high-flow exhaust systems. Many power packages allow for customization by choosing different cam profiles to tailor the power delivery to your riding style, whether you prioritize low-end torque or high-end horsepower. Most 124 in. power packages are designed as "bolt-on" kits, meaning they can be installed without requiring extensive engine machining, making the upgrade process relatively simple. Select the 124 in. power package kit with chain drive cam designed for your application.

Not Yet Reviewed

$3,265.95

S&S Cycle 124 in. Power Packages with Gear Drive Cam

S&S Cycle 124 in. power packages with gear drive cam are the ideal combination of performance and savings to transform a Harley-Davidson® motorcycle without breaking the bank. Each kit is tailored with the necessary components for your specific HD® model. These kits offer significant benefits, including a substantial increase in horsepower and torque across the powerband, improved throttle response, better cam timing accuracy due to the gear drive mechanism, and a more reliable valve train compared to a standard chain-driven cam, making it ideal for riders seeking a powerful and responsive engine upgrade, especially on larger displacement bikes like the Milwaukee-Eight models. Installing a 124 in. power package often necessitates additional tuning adjustments, including adjusting fuel delivery and ignition timing to optimize performance. Select the power package with gear drive cam designed specifically for your HD® model and engine to ensure proper fitment.

Not Yet Reviewed

$3,460.95

$3,695.95

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